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Zothecula writes "While quick charging technology installed at strategic points along a planned route might be a good fit for inner city buses, it's not going to be of much use to electric vehicles that stop infrequently. Volvo sees our future long-haul trucks and buses drawing the juice they need from the road itself, making large onboard batteries a thing of the past. 'The two power rails/lines run along the road's entire length. One is a positive pole, and the other is used to return the current. The lines are sectioned so that live current is only delivered to a collector mounted at the rear of, or under, the truck if an appropriate signal is detected. As an additional safety measure, the current flows only when the vehicle is moving at speeds greater than 60 km/h (37 mph). "The vehicle is equipped with a radio emitter, which the road segments can sense," explains Volvo's Per-Martin Johnansson. "If an electric vehicle passes a road segment with a proper encrypted signal, then the road will energize the segments that sense the vehicle.'"

Wasn't there some scheme a few years ago someone came up with that used the concept of charging cars by putting magnets under the roads so that as the cars passed over them it would induce an electric current in coils contained in the undercarriage? Seems like that would be a lot safer and cost-effective than rolling out electric rails, and wouldn't require physical contact.

looks impractical, to be honest. might be suitable for some routes, but for those you might just as well put over the road electric rails(some busses in russia do this, or at least did kinda like tram on rubber wheels). they claim this system is used on some trams too, not sure if those trams are on rails though which makes it a lot simpler and reliable.

I'll admit I dindn't RTFA, but I imagine the "rails" being discussed are power rails, a concept completely independent from railroad rails - i.e. they do nothing to keep the car on track, they just provide power so long as the brushes are in contact.

As such the big advantage I see of in-road rather than overhead power rails is in aerodynamics. To access overhead power rails you need some sort of big aerodynamically ugly arm reaching up to the rail, potentialy drastically increasing power losses to air resi

they say that the power rails in the road rather than in the air are cheaper.

I just find that unlikely, especially anywhere with occasional snow and long cycles of road repairing.. yeah it gets structural reinforcement but it gets to take a lot more abuse and different kind of structural stresses as the road lives during seasons.

the thing is the siemens type system is used for public transport with busses in many parts of the world and has been used for decades.

You need an appropriate device on your car to activate the power to the rails on your section of the road. This gives a great opportunity to track your vehicle, where it is, what speed it's travelling, how much energy it's using and then send you a bill as a sort of dynamic road toll for the use of the road, a bill for the energy you used and the fines for exceeding the speed limit all without actually having an officer present.

Wouldn't mind it, though, if the system were intelligent enough that I could tell the car where I wanted to stop and then it could take care of the details of getting me there and wake me up from my nap once we get within a few miles of the destination. If the car's driving while I'm napping then they can send any moving violations to the company that built the car and its software.

I'd assume passenger cars using this would sill have batteries. If the system can provide enough juice to run the car and charge the battery, you don't actually need the system on 100% of the roads. What about just putting it in front of intersections in the city where cars sit for several minutes?

If it doesn't kick in until 30+ MPH, then most likely the trucks will keep their diesels (maybe reconfigured as a diesel/electric series hybrid, or something), so they use

Actually I'd think highways would be the better example, especially considering even the summary mentions long-haul trucking. Use your batteries for getting around town where you don't really need much range (who drives even 50 miles/day on city streets? Delivery people maybe?), then get unlimited range while on the highways and be fully charged when you get to your destination and go back to unpowered streets.

Seems to me that eliminating the battery entirely is unlikely, but that this could be used in conjunction with smaller batteries to solve the "range anxiety". You're good to go with your batteries for your daily runaround routes (including getting off the highway to pee), and you use the highway's power for your inter-city travel. The car would be far cheaper if it needed only 50 miles worth of range rather than 300.

You might even be able to charge your battery, eliminating the need for a charging station a

Exactly! Well, assuming you are refering to some sort of fleet of magical private trolleys which can leave their tracks at will and power themselves off stored power as they drives around unpowered streets and then reconnect to the power rails when they're back on the highway/other powerd street of course.

well.. it doesn't electrify unless you got a rfid tag of sorts on your vehicle transmitting that "YO, GIMME SOME POWER MY ID NUMBER IS 23423" and in addition to that it doesn't electrify unless you're moving at such a speed that you would be hitting anyone standing on the rails anyhow.

While quick charging technology installed at strategic points along a planned route might be a good fit for inner city buses, it's not going to be of much use to electric vehicles that stop infrequently.

Ya, that sort of thing hasn't really worked out for petrol-type vehicles at all. If only there were places I could buy gasoline (or electricity) along the way... Oh well, one can dream.

Since a typical electric car needs about 5x as many fill-ups as a typical gasoline car, you'd need five times as much 'refuelling' capacity. And since they take about ten times as long to charge, those cars would be staying at those 'refuelling' stations for ten times as long.

Electric cars are a silly idea until we have Mr Fusion units or batteries made from unicorn farts.

If we're going to go through the trouble of laying down electric rails on the highway, why not just put down actual rails so we don't have to steer the cars either. have a system where the car can attach/detach from the rails so that it can move between traditional roads and roads with rails. Basically it would work like those electric slot car racers, except you'd want to engineer it so it the car wouldn't fly off the track in a corner. The car would then just retract the mechanism that fits inside the slot when it wants to go on traditional roads. You could have an electric car that has it's own batteries for short trips, but gets power from the roads when going on longer trips.

while i agree finding affordable solutions to retrofit existing vehicles for alternative energy should be a near-term priority, I detest the idea of the long-haul truck as being anything sustainable. we have an entire infrastructure of bought-and-paid-for rail that stretches across the nation to deliver goods. its already partially electric by virtue of its diesel to electric locomotive propulsion system, and could be almost trivial to convert to a hybrid electric system that returns energy to the grid. eventually going full electric would be largely feasible and we'd take some of the largest polluters off the roads in the process.
volvo might use this technology to create rechargeable cities. for example: san diego is a charging city, but once on the freeway you're "wireless" and running off the battery. upon entering say, downtown los angeles, you're in a charging city and running off the grid. grid fees are integrated with parking fees, etc..

A lot of the energy advantages of rail can be found in automated vehicles. If they travel close enough together they can use much less energy. The only real "waste" is the additional friction of rubber tires versus metal on metal rails. This could eventually be overcome as well with technology advancements in tire technology. You could even run on very hard low traction tires that either brake in unconventional ways or soften up when needing to brake. No reason to tear up the existing infrastructure because

For long-haul bulk freight, rail is astonishingly efficient. Nothing you can do with trucks comes anywhere close. Rail is pretty useless for that last mile, of course, but for long haul it's a bit of a mystery why it doesn't get more use.

No - rail is more efficient because of:* Steel wheels on steel rails.* Very large engines, with the power-to-weight ratio of the engine barely a concern.* Fewer intersections/interchanges and less traffic: fewer reasons to need to brake and re-accelerate.

None of which applies on the scale of passenger cars, or on a "network" with an endpoint in every driveway (or even every neighborhood). Other than the steel wheels, the efficiency is possible precisely because there are limited routes and endpoints, cargo

True, but have you looked at steel prices lately? If the current trend continues we will eventually be unable to afford to build and maintain rail lines because of the price of the rails. Also, the price of copper is high enough that we'll soon start to see drones patrolling electrified rail lines to prevent copper theft, because electrified rail lines have lots of copper wire that's not at high voltage, and thieves have caught on. (Id' imagine electrified roads will have to be patrolled too unless the copp

They want to start with the trucking industry.
That means they will have to remove each and every tractor (the driving part for you non trucking people) from the road and replace them with a suitable tractor.
This tractor will need to have the current engine for long hauls and the electric for inner city travel as they currently perform both.
Or you will need to build transfer point just outside of cities where the truckers can unload, transfer to smaller hybrid trucks to utilize this.
This would be fantas

You will find conventional flow notation followed by most electrical engineers, and illustrated in most engineering textbooks. Electron flow is most often seen in introductory textbooks (this one included) and in the writings of professional scientists, especially solid-state physicists who ar

This has been tried before. It's called a ground level power supply. [wikipedia.org] Trams in Bordeaux use it. The sections are powered on and off in 8-meter sections. When a section is off, it's grounded. For safety, there are two levels of switching. The 8-meter sections each have their own power control box, and there's a second level of control which monitors a number of sections and will cut power for many sections if something is live that shouldn't be. The trams have battery backup so they can get through dead sections. Bordeaux only uses the system in their scenic historic area. Once out of that area, the trams raise pantographs to connect to overhead wire. Two other small cities in France have installed that system, but only short sections in the city center use that system. Dubai is putting in 14km of a similar system.

Drainage, water, and ice are big problems. (Not in Dubai, though.) So is cost. There's a lot of high-voltage switchgear involved.

One aspect of solar power is the question of where to put the collectors. Land area is expensive and in short supply around cities, and putting the collectors close to where the energy is needed makes better efficiency.

It occurred to me that we have lots of land in the medians between highways, many of which are enclosed by guard rails or Denver barriers. The road already has easements which could be used to run powerlines (metal conduits at ground level, no digging needed).

I'm guessing this system meters which car used X amount of electricity and bills accordingly? You pay what you use, right? Or is this some sort of ploy to charge each tax payer a flat monthly fee across the board?

What if I want to go somewhere there is no infrastructure to power the car? What if I don't want my tax dollars going to the probably trillions of dollars necessary to install this everywhere? What if I don't think it's a good idea to have powered rails carrying hundreds (maybe thousands) of volts along major roads? If there's a glitch somewhere, then everyone on that road is stranded? I could go on. I think this is a really dumb idea. Focus on better, higher-density, longer-lifespan battery technology instead.

So every single road needs power lines along it on both sides so tall trucks an cranes can't make a left or right turn anywhere ever. Then when the power goes out, you can't drive anywhere. Then it's one unbelievably large target for hacking and terrorism so no home electricity OR transportation. This is quite possibly the stupidest idea since flying cars.

You most certainly are ridiculously stupid! Try reading the article before calling ideas "stupid". The idea may well not work out but not for the reasons that you cite. Try reading the article and then thinking for a bit and then commenting. Then people won't think you are an idiot.

To those making fun of it, it is *not* a railroad/railway, nor is it slot cars. The vehicle is not on a fixed track.

Railways have had "third rail" power supply systems for a very long time. The biggest issue with them is safety; miles and miles of exposed high voltage terminal that will fry you if you touch them. Ouch. The mitigating factor that makes them a sensible option for a railway is that the railway is dangerous enough even without them that it needs to be fenced off.

This invention is basically giving this system to the roads.

The important point here is that the power is only activated for very short stretches of track at once, when that stretch is directly underneath the vehicle. This makes it safe enough to put it onto the public roads where you can't fence it off.

What it *won't* do is give us battery-less cars any time soon. We might be able to get away with smaller batteries, but we will still need them. The summary states that it won't provide power if you're going at low speed. That means city drivers could go an entire journey without being able to use the system, and even for journeys where you can use it, you'll still have low-speed parts of your journey. Even if we decided to start building it now, it will be many decades before it has widescale coverage; there will be plenty of minor roads that are likely never to be upgraded (there are plenty today that are still dirt-roads). And of course, your own driveway probably won't be connected to the grid either.

The beauty of this is that it is entirely compatible with the existing road network and could be implemented piecemeal. Roads could be upgraded with the system. Cars that can use it would benefit, but older cars could carry on using the same roads just the same as they always have. Likewise, if the electric cars also have a battery, they would be free to continue using roads that didn't have the electric rail as well as those that do.

My prediction is that it will be used initially for bus routes. If all the bus routes in a city like London were converted, it would amount to a significant amount of track. The fuel savings to the bus operator would make it very easy to pitch to the city. Existing electric and hybrid cars owned by the public could then be retro-fitted with power pickups for the system, and where the bus routes are public roads, people could benefit from the same fuel savings. If this was subsidised on the grounds of reducing pollution in the city, then the public take-up for the project would likely be quite big.

As the number of vehicles capable of using the system increases, the road network could be further upgraded beyond just the bus routes.

So yes, it is a clever system. However, don't be fooled into thinking it's a new idea. This system was first used a decade ago for a tram line in France. It was the first electric tram line in the world not to need overhead power cables. Ground-based power lines had never previously safe enough for a tram line that needed to run through city streets. This system has been in use for a decade now and has proved itself well. Building it into the regular road network seems to be the next sensible step.

"the current flows only when the vehicle is moving at speeds greater than 60 km/h"
Push starts just got a whole lot more desperate. Aad/or funnier looking to watch.
Wait, nobody these days knows what push starts were. Only people of a certain age will mod this one.

Two big problems with battery-based EVs are the battery itself (weight, expense, lifespan) and how long it takes to charge. Sure Tesla is working on their quick-charge stations, but even those are only quick compared to plugging in overnight - compared to pumping 10 gallons of gas, they're *really* slow.

Capacitors could address some of that, but the energy density is too low - you need to charge them frequently. Some kind of road-based "kick charger" to top them off quickly could have a lot of potential.

Actually I can imagine a lot of very good uses for commercial use of battery powered trucks. One item is in forcing the drivers to actually obey routes and time schedules. As it is drivers normally cheat and spend too many hours on the road without rest. If a phone home type of system is built into the charging stations the trucker will be forced to take breaks, will have to stay on route as he would not be allowed to charge at other stations and hijacking a truck would not get the thief wher

I certainly agree, there's unlikely to be an economic breakeven for most roads. But most people don't travel long distances on most roads either - they do so on highways. And any highway that sees a lot of traffic (trucking at first) is a viable candidate. It makes the highway range of electric vehicles effectively infinite, and you can still top off the battery at home/charging stations for the rest of your driving.

If one assumes that this is the solution for electric cars, then a logical extension is that everybody will adopt it. Intercity truck hauling is the low hanging fruit so that is where you start. Then it cascades down to everybody. In 20 years half the cars driving would use the technology.

Initially costs would have to be subsidized by the taxpayers, but as usage grows then subsides would disappear with costs being recouped by charging for the electricity.

It’s a long shot but there could be huge wins. That is how I would evaluate it.

I will agree with you that batteries (or better yet, ultracapacitors) are the more likely solution, but they have gaps.

Cars work. Busses that travel along prearranged routs work either by battery swapping or fast charges at bus stops.

Trucks don’t work, or at least not as well. I different solution is going to be needed. If this is the solution for trucks (which I am not sure of) then would think it would be a simple add on for cars. Batteries for short trips, power from the road when on the highway. They would not be incompatible, but there would be some tradeoff for the extra weight..

Ultimately it's not going to work because rebuilding roads to fit all this crap underneath them would be insanely expensive compared to pretty much any other alternative. It might be viable in towns where the roads are close to capacity all the time, but stringing up overhead electrical cables would almost certainly be much cheaper. The idea that you'd rip up hundreds of miles of road between two North American cities to fit complex electrical systems under them so a few dozen trucks an hour could drive along there using electricity rather than diesel is simply laughable.

I'm really not sure if the name "diesel engine" is appropriate for the resulting contraption. But, yeah, natural gas could be of some use here, although I still think that nuke-powered trains still seem like a better idea to me (as in, we already have them so there's no need to change the infrastructure, and the squirrels and badgers in the forest will thank you for not polluting the atmosphere).

The idea that you'd rip up hundreds of miles of road between two North American cities to fit complex electrical systems under them so a few dozen trucks an hour could drive along there using electricity rather than diesel is simply laughable.

More like a hundred or more every hour during the day, and a few dozen an hour late at night. The number of trucks traveling over the highway system in Oklahoma is staggering, and having electrical systems under the highways would be well worth the money. As for ripping up the highway, they do that anyway on a regular basis to ensure maintenance and safety. If half the vehicles on the highway converted to electric it would be worth the money in the end.

having electrical systems under the highways would be well worth the money

The Tesla Model S with a 85kWh battery has a claimed range of 500km travelling at 90kph (55mph). That means it uses about 15 kilowatts to travel at 90kph.

Thus to charge the 85kWh battery within 1 hour while driving at 90kph, you'd have to supply 85 kilowatts (to charge the car) + 15 kilowatts (just to keep the car moving) for one hour. After including transmission and battery charging losses it'll be well over 100 kilowatts.

Assuming the cars aren't tailgating each other and forming a road train, you'd have

But why would you need to recharge while driving? Okay, sure it'd be *nice*, but it doesn't buy you anything but minor convenience. All you need to do is keep it rolling, so 15kW would be plenty to give the car unlimited highway range, and you can then reduce the battery capacity drastically since it's very rare that anyone will travel anywhere near 500km without using highways. Topping off the battery can still be done in a less infrastructure-intensive manner for driving around town.

It might be viable in towns where the roads are close to capacity all the time, but stringing up overhead electrical cables would almost certainly be much cheaper.

But that doesn't make too much sense. In cities, batteries are the best option anyway since the travel distances are short. It's the long distance routes where direct energy supply turns out to be advantageous.

An interesting concept but it seems very unlikely this will be a prefered solution in 30 years as battery technology improves.

One problem with nerds that are living in the age of Moore's Law, is that they end up believing that other technologies enjoy the same sort of exponential improvements as semiconductors. In general, they do not. There will almost certainly be some incremental improvements, but I wouldn't bet on any big breakthrough in battery technology. If you look at the periodic table, there just isn't anything to the left or above lithium, except hydrogen which isn't practical for a number of reasons. It is extremel

You don’t need to go anywhere on the periodic table. Automobile parts (such as the hood of a car) have been made from carbon fiber that serves as ultracapacitors. The problem is manufacturing them economically.

Indeed. Moores Law works because the technology we're improving is also the core technology we use to make further imrovements. There's a few informatic-driven fields which piggyback on semiconductor technology to enjoy similar growth, and even a few which enjoy even faster growth over limited timeframes due to other enabling technologies or business climates getting them into the game only recently so they enjoy retroactive benefits (gene sequencing springs to mind). But by and large anything that depen

There was a recent news items article [i4u.com] for Lithium-Sulfur batteries with 4 times the capacity of today's.

There are lots of things that work in the lab, but are impractical in the field. Will this battery work at -50F in Fargo, ND? How about at 120F in Las Vegas? Will it handle 3000 discharge cycles? Will it be safe if it ruptures in an impact? Will it degrade if it is left fully discharged in an airport long-term park lot for three months? Very few batteries meet these criteria.

IIRC Slashdot had an article talking about doing something like that today.

If was for busses that would be charged at bus stops. Bus stops are a lot closer, are know in advance, and are for a decent length of time. There were using normally batteries and not suppercap and induction to charge, but you need to start somewhere.

>this would reduce the infrastructure cost of the strips by quite a bit

Probably not by much actually - you still have to deliver X Wattage per mile, and now your chargers have to be *far* better conductors. For mathematical convenience lets say the intermittent chargers were only 1/10 as common, say running for about one block per mile. To provide the same charging capacity they have to conduct 10x the power, which means 10x the cross-sectional area, so the net material amount in the charger is the sam

I think the idea of using this infrastructure to charge batteries would be useful. If the power provided would serve to power the car and enough surplus to charge the battery you would never need to stop at a fuel/charge station again.

Not really - the part that is new is being able to bill every car seperately for it's power draw and reject freeloaders, rather than simply having the same company operate all the cars and infrastructure so that apportionment is a non-issue. The safety part is simply a free side-effect of that, with the cutoff speed being pretty arbitrary.

If one assumes that this is the solution for electric cars, then a logical extension is that everybody will adopt it. Intercity truck hauling is the low hanging fruit so that is where you start. Then it cascades down to everybody. In 20 years half the cars driving would use the technology.

Initially costs would have to be subsidized by the taxpayers, but as usage grows then subsides would disappear with costs being recouped by charging for the electricity.

It’s a long shot but there could be huge wins. That is how I would evaluate it.

I can see a couple of 'gotchas' already.

First, those are conductors embedded in the road. They'll be exposed to the weather and climate. What happens when a snow plow drives over it scraping snow away from the road bed? Won't the blade short out the strip? Can it get all the snow and ice off the conductors? Will there be shorts when a vehicle activates a strip? What happens if a strip goes dead for a bit? Are they going to be designed short enough that momentum will take the vehicle to the next strip?

How are you going to power this sucker?

This is an interesting concept, though, a way to get engineers thinking outside the box. But why use strips embedded in a road surface when you can build maser towers and beam power to a rectenna installed on the vehicle?

It will likely start with the city bus system funded by taxpayers. Just move the overhead power lines underground on selected routes to test the concept. The encrypted signal is so other users can't steal the power without a subscription. Quick, someone patent storing energy in a capacitor so you can get the car/truck/bus the next 100 yards down the road.

Not possible. The only way that would be possible is if you've got millions of individual power cells that the car is charging from as it goes. With the cells turning on and off in response to the signal.

So, I guess it's technically possible, but the likelihood of getting a device like that to function would be pretty much nihil.

A better move would be to just charge a tax based upon the distance driven and the type of vehicle, knowing approximately how much juice the vehicle would be using to cover the dist

Sadly probably no. Piezoelectric works because of an elastic spring when pressure is applied. Increasing the elastic spring of a road increases rolling resistance, which decreases the efficiency of the car, resulting in a net energy loss.

I'm not so sure about that, the cars already cause the ground to vibrate a bit. Absorbing some of that and converting it to electricity would be a net win. Especially in places like Athens where the vibrations are damaging ancient buildings.

They already have that kind of thing [wikipedia.org] for railroads, really. Instead of powering on an alerting system it would power on the energy delivery system. That's the harder part, not the encryption and selectivity.

Because that would impose staggering losses in the energy transfer. Inductive (magnetic) transfer of energy is not very efficient when there are air gaps involved. You can do it, but you are going to waste a LOT of energy. You do solve the problem of having large voltages touchable by the public.

Of course... One could just produce a magnetic system to push the cars forward in a linear motor setup and avoid much of the transfer losses. Just imagine the automated traffic control you could have with being

Completely agreed until>Or... Just do what we've done for years and put wires up in the air over the road.

Do you really want to deal with everyone in town evenutally having trolley-style power arms sticking out of the top of their car? Not to mention the potential infrastrucutre damage when these people repeatedly connect and disconnect to a dangling power cable. How long do you suppose it will be before someone gets their power-arm snagged on the cable and drives off without noticing?

I think volvo, and most people, forget that the benefit of fuels (solid, liquid, or gaseous) is that they are very cheap to transport. Electricity, on the other hand, is insanely expensive to transport. Think about a 10% loss for every major hop. The middle of the road in a large city is likely 4 major hops from the power plant. That takes 100 down to 65. That's up to a 35% total loss.

It took me all of thirty seconds to find a quote on that:

Transmission and distribution losses in the USA were estimated at 6.6% in 1997[10] and 6.5% in 2007.

You, sir, are bonkers. Of course they slow the wind locally! What's the problem? They are actually relatively cheap in maintenance (you can look up the financials of a modern wind turbine park if you don't believe me, we're talking maybe 1-2 US cent per kWh), as for the rest of your points, that's generally why you put them away somewhere far.

Solar panels take up a huge about of territory, polute to manufacture, and require total replacement to upgrade.

So you put them in a desert. "Polute to manufacture" - maybe but they're still a net win. "Require toal replacement to upgrade" - so what?

I think volvo, and most people, forget that the benefit of fuels (solid, liquid, or gaseous) is that they are very cheap to transport. Electricity, on the other hand, is insanely expensive to transport. Think about a 10% loss for every major hop. The middle of the road in a large city is likely 4 major hops from the power plant. That takes 100 down to 65. That's up to a 35% total loss.

These numbers clearly came from a questionable source. (perhaps your backside?) The PDF available here [abb.com] indicates a transmission and distribution loss of between 6% and 8% for the United States power grid.